1. Field of the Invention
Embodiments of the present invention generally relate to laser scanning systems and more particularly, to determining the oscillation frequency of a scanning flipper and adjusting the flipper's oscillation frequency in electronically-controlled damped off-resonant laser based symbol scanning mechanisms.
2. Description of the Related Art
One commonly used beam scanning technique involves driving a resonant element bearing a mirror into oscillatory motion within a plane, while a laser beam is directed incident the mirror surface. As the resonant element oscillates, so too does the mirror, causing the incident laser beam to be scanned across a scanning field of substantially planar extent, as well as a bar code symbol disposed therewithin. Some scanning mechanisms utilize strips made of MYLAR® or KAPTON® plastic material to realize resonant scanning elements.
In general, laser light reflected from the scanned bar code symbol is collected and detected to produce an electrical signal representative of the scanned symbol. Ultimately, the electrical signal is processed in order to decode the scanned symbol and produce symbol character data representative of the decoded symbol.
A benchmark oscillation frequency is set during production. However, during use the actual oscillation frequency of the scanner may deviate from the benchmark oscillation frequency. When a significant deviation from the benchmark frequency occurs, the scanner will not transmit or receive information properly.
Therefore, there is a great need in the art for an improved laser scanning mechanism which avoids the shortcomings and drawbacks of prior art laser beam scanning apparatus and methodologies.